Is there any good example and clear concepetion regarding nested for loop ?

Question

Nested for loop as can be draw multiple diamond pattern in one code.

Answer 1

yep, try processing how you can draw a diamond on a paper with a series of dots, using your own instruction one at a time like you want the diamond to be, like "when 9 is input, i use 9 space or more to get the pattern in the middle which will be controlled by a single for/while statement and another to print the star while you increment from one to 9 creating a triangle, and then create another inverse triangle to form a diamond using the same criteria earlier but in this case it start from 9 to 1" i hope you get this little explanation

Answer 2

Well the for loop simply keeps on executing the lines it covers again and again until the condition remains true...
Now , put in another for loop into those lines of code and we get a nested for loop structure.
Now with every iteration of our 'Parent' Loop the child loop will execute a variable number of times...